Skip to Main Content View Text-Only

The City of Portland, Oregon

Portland Water Bureau

From forest to faucet, we deliver the best drinking water in the world.

Customer Service: 503-823-7770


More Contact Info

Double Check Valve Assembly

The Double Check Valve Assembly (DCVA) is essentially two single check valves assembled within one body and furnished with four test cocks and two shut-off valves.

Double checks are commonly used to protect against low to medium hazard installations such as food processing equipment or lawn sprinkler systems. They may be used under continuous pressure and protect against both backsiphonage and backpressure conditions.

A diagram of a double check valve is illustrated below:

Installation Type Above and below ground, but no more than 24" deep or 5' above floor or grade respectively
Safe to inject chemicals into system?  No
Okay to locate control valves downstream?  Yes
Okay to locate backpressure source downstream of assembly?  Yes
Installation height in relation to highest downstream piping:  At point of connection
Number of assemblies required  One per system
Use only in low to medium hazard applications?  Yes
Testing required after installation: annually
Testing required after repairing or moving assembly?  Yes
Cost:  Varies